1. Field of the Invention
This invention relates to a new and improved plastic cap for a large container such as a 5-gallon water bottle having a partially external tear groove. More particularly, the invention relates to a cap which fits over a conventional large bottle neck by a snap-on action. The cap is tamper-evident in that the lower portion of the cap must be torn off before the cap can be removed. Accordingly, the cap is formed with a horizontal score line and a downward-extending second score line which terminates at the bottom edge of the skirt of the cap. The cap, preferably, but not necessarily, adjacent its lower edge has an internal seal bead which seals against the neck of the bottle. Accordingly, the second score line comprises an external groove in the outer surface of the cap and then becomes an internal score line extending upward to the internally scored horizontal score line. Where a lower bead is used, the transition from external to internal score line occurs after it crosses the lower bead.
2. Description of Related Art
Caps of the above-identified general type have been widely used in the bottled water industry for many years and are evidenced by such U.S. Pat. Nos. as 3,392,860; 3,392,862; 2,840,137; 3,979,002; and 4,911,316. Thus, the exterior of the neck of the bottle has a convex upper bead near the top lid which merges into a concave portion below the top bead and then merges into a convex lower bead. The cap has a top disc which engages the lip of the bottle and an outward bulge below the lip which fits over the top convex neck bead. The skirt of the cap below the bulge extends downward and engages the lower convex neck bead. Once the cap is snapped in place on the neck, it cannot be removed without tearing off the lower portion of the skirt and thus the cap is said to be tamper-evident. In order to remove the lower portion of the skirt, a horizontal score line is formed on the interior of the cap below the bulge and a downward curved second score line extends to the bottom edge of the skirt. By pulling a tear tab which projects below the bottom of the skirt adjacent the bottom terminus of the second score line, the cap may be torn upwardly along the second score line and then at least partially around the horizontal score line, making it possible to remove the cap.
The present invention differs from these prior art references in that the second score line extending up from the bottom edge of the skirt is external, whereas the remaining portion of the second score line and the first score line are internal. Hence there is no interruption of the lower seal bead of the cap which would otherwise interfere with the integrity of its sealing function. Thus if there is an irregularity in the surface of the lower convex neck bead--such as a mold parting line--the integrity of the seal is not affected.
Optionally, the cap has an internal second bead. The integrity of this bead is not affected since the second score line is on the outer surface.